What is Database.AllowCallouts in Salesforce?

Hi Aditya,

Database.AllowCallouts are used to allow Callouts in batch Apex, “Callouts include HTTP requests as well as methods defined with the web service keyword”. To use a callout in batch Apex, specify Database.AllowsCallouts in the class definition. For example:

global class SearchAndReplace implements Database.Batchable<sObject>, Database.AllowsCallouts{
}

For further details refer to this link :
https://www.salesforce.com/us/developer/docs/apexcode/Content/apex_batch_interface.html